More ideas from
The milk jug is half full of salt water. So it floats and doesn't freeze. The horses have learned to push the jug down to access the water

To avoid completely full, frozen water troughs and ensure that there is always access to open water (which is hugely important for horses any time of the year) simply fill a jug half full of salt water. It will always float and never freeze.

Don't place the saddle too far forward, on top of the shoulder blade--great article should be read several times.

Saddle Placement: Avoid placing the saddle too far forward on top of the shoulderblade

Hay feeder

Maybe using a slow feed hay net on the bottom might work, not that expensive to try for a diy hay feeder.